1. No Batteries Required: The wireless doorbell transmitter uses unique technology. Pressing the button converts kinetic energy into an electrical signal to ring the doorbell wirelessly, helping avoid battery-related concerns. It offers more convenience, energy efficiency, and practicality compared to older models. 2. 45 Chimes & Melodies: There are 45 classic chime melodies available, with adjustable volume control and a diverse selection to meet different needs. It has 4 adjustable volume levels from 0dB to 90dB, which is sufficiently loud for seniors to hear. The pleasant melodies play each time someone rings the doorbell, and the LED indicator provides a visual notification, a useful feature for the hearing impaired. 3. IP44 Waterproof: The transmitter has an IP44 waterproof design, made of ABS material that is non-toxic, safe, and recyclable. It operates within a temperature range of -20℃ to 65℃ and can withstand various harsh weather conditions such as sun, rain, snow, and frost. It is widely used in homes, offices, hotels, villas, hospitals, study rooms, apartments, schools, and other appropriate areas. 4. Long Wireless Range: With a 150M/500FT wireless range and 2 included plug-in receivers, this doorbell does not interfere with other devices in the home or neighbors' devices. It helps ensure you do not miss a visitor, even when you are a few rooms away or on a different floor, making it suitable for large homes, warehouses, offices, etc. 5. Easy to Use: Designed for convenience and ease of use, the doorbell can be attached next to the door using the included double-sided tape or the cover can be mounted to the wall with a screw. Then, simply plug the receiver into a power outlet.